Why Historical Maps Still Matter So Much, Even Today
With 150,000 or so old print maps to his name, David Rumsey has earned his reputed place among the world's "finest private collectors." But the 69-year-old San Francisco collector doesn't have any intention of resting on his cartographic laurels. He continues to expand his personal trove as well as the digitized sub-collection he makes open to the public online — some 38,000 strong, and growing.
"I'm pretty old for a geek map guy," he says. "But I stay young by embracing new technologies all the time."
Rumsey, a native New Yorker, began his career teaching and practicing art — specifically, its intersections with technology — before getting involved in a charity on the West Coast. After starting his map collection Rumsey used that early art-tech interest to stay ahead of the digitization push. He's created a series of interactive maps that layer old prints onto the Google Earth and Google Maps platforms, and this summer he plans to launch a geo-referencing tool (similar to one recently introduced by the British Library) that lets users get involved in the digital mapping process themselves.
While preparing for this next expansion of his online map empire, Rumsey remains fascinated by "the power of putting these images up and letting them go," he says.
"Maps have a way of speaking to people very straightforward," he says. "You don't have to have a lot of knowledge of map history or history in general. To me they're perfect tools for teaching history to the public."
Screenshot of London 1843 from the David Rumsey Historical Maps Collection.
What draws you to a particular map so much that you decide to add it to your collection?
So what draws me to a particular map is how is it showing real space. How can we use it to measure real space? How can we use it to imagine that we're standing in real space? How does it accomplish that? To me, this is totally arbitrary, but I chose the date of about 1700 to begin my map collection, going forward right into present day. Because around 1700 is when you have the real rise of scientific mapping. That means using surveying tools, using triangulation, to really be able to make a map on which you can do reliable measurements and show space as if you're standing in it.
Screenshot of San Francisco 1915 from the David Rumsey Historical Maps Collection.
You're a big proponent of open access. Why do you feel it's so important to make your maps available to the general public?
I think open access for anything — maps, art, books — is an incredible opportunity that the Web allows us to accomplish. It's kind of introducing the public to what I call in the academic world primary sources. The original map, the original book, all of which we've had in our libraries in special collections for hundreds of years, but they've never been available to general public.
The typical post in Twitter about my site is: uh oh, you're going to lose a whole day. Losing a day — think about it. If we didn't have the internet and these viewing technologies, how could you spend a day with these maps in the physical world? You'd have to travel to an archive, they'd have to pull them out. Here you can search on whatever your interest is.
Screenshot of St. Petersburg 1753 from the David Rumsey Historical Maps Collection.
Your Google Earth Collection layers old maps onto new technology. Talk about the process of making them.
First you have a scan of the old map. You open that in a GIS program that is made for doing this geo-referencing. Essentially one window has the old map in it and a window next to it has a new map — a modern satellite view or a modern street map or regular map. Then you use tick points. So I'll take the tip of Florida on the old map and put a tick, and take the tip on the new map and put a tick. You're doing 60 to 100 points. Then you tell it to recalculate the old map into modern geographical space using those 60 to 100 space. And it rebuilds the whole image. So now you can open it in Google Earth. It will automatically appear in the right spot.
Screenshot of Paris 1834 from the David Rumsey Historical Maps Collection.
What do you hope casual viewers, who don't have your experience reading maps, take away from these projects?
To be able to compare the past and the present in a way they've never been able to do before. People look at old photographs of a city. They say: Oh, this is what 5th Avenue looked like in New York City in 1910. Interesting. Old cars. So on. But if you look at the map of the same area, compared to the map today, you look at all the buildings completed, look at the alleyways closed off. You get another way of looking. So I think people sense the change over time.
What is it about the past, more specifically, that you think old print maps can teach us? Is it just something about cartography or something bigger about humanity?
Oh I think it's something bigger about humanity. … These old maps, think of them as archives. Each map is an archive of information.
We put online the "Karte des Deutschen Reiches 1893." This is the national map of Germany created after German unification in the early 1870s. … The Germans are maniacally thorough in everything they show on this map. You can see not just forest cover but five or six kinds of forests. Pine forests are one symbol. Deciduous woods are another. Different grassland, different swamps, all the major public buildings. I was saying, this is an archive of information arranged spatially that you're not going to find anywhere else.
What we do now with text, it's called OCR, Optical Character Recognition — this is what Google does with Books online, it's indexed every word on every page. Imagine if we could do that with maps like any of these geo-referenced maps. If we could start building a database of all kinds of forests. Then we can say there were, oh, one million hectors of pine leaf forest in Germany in 1893. Or make a list of names of all the towns.
Detail of Sheet 269 - Berlin - Karte des Deutschen Reiches 1893
You could probably measure, with regard to climate change, how much different things are.
Certainly they're going to show coastlines, which gets you to inferences about sea level. A lot of them show forest cover. Probably things we can't even think of. I'm hopeful that Optical Character Recognition technology will come about in the next decade. It's pretty tough. A lot of people are working on cracking that problem. With books the texts all go in one direction. It's easy for a bot to catalogue it all. In maps it goes in every direction and we use completely different fonts. One for a river, one for a city of X size, another for a city of Y size. But all that should be capable of being known in terms of computation. That gets me pretty excited.
All maps courtesy of the David Rumsey Map Collection via a creative commons license.